Overall Water Quality

The Company carried out a total of 14,365 National and Directive determinands during 2006. Of these, 99.98% met the relevant water quality standard, but three showed a PCV to have been contravened. A privately owned galvanised supply pipe caused the exceedence for Iron in Rhos zone.

Coliform bacteria were detected in two zone samples; these were confirmed as total coliforms and all resamples taken were satisfactory from the exceedence in Brymbo high zone. The exceedence in Wrexham zone led to resamples being taken, in which one demonstrated a total coliform exceedence. Further resamples were obtained and the exceedence was demonstrated to be caused by the consumer’s tap. Two E.coli bacteria were detected at Penybryn service reservoir (this counts as a total coliform failure and an E.coli failure). In response to this the Company took Penybryn out of service then inspected and cleaned it. All samples taken in response to this were satisfactory.

No coliform bacteria were detected in any of the Company’s treatment works.

Three treatment works are continuously monitored for Cryptosporidium in accordance with Regulation 29. The treatment standard is set at one oocyst per ten litres of water. 1,103 samples were taken during 2006 and only five samples contained any oocysts. In all cases it was only one oocyst in over 1000 litres of water and no sample came close to breaking the one oocyst per ten litres PCV.